1. Field of the Invention
The present invention relates to a disk reproducing device for reproducing information recorded on an optical disk such as a compact disk, a laser disk and the like.
2. Description of the Related Art
FIG. 11 is a schematic perspective view to show outside constitution of a conventional disk reproducing device and FIG. 12 is a schematic perspective view to show inside constitution of the conventional disk reproducing device shown in FIG. 11. Here, in the drawing, it is assumed that a lower right side is a front side and an upper left side is a rear side. In this respect, it is assumed that this relationship is common to the following respective perspective views.
In the drawings, a reference numeral 1 denotes a chassis to constitute box of a disk reproducing device, 2 denotes a disk inserting opening which is made in front side of the chassis 1 and through which a small-diameter disk such as 8 cm disk or a large-diameter disk such as 12 cm disk is inserted, 3 denotes a disk transfer part provided near the disk inserting opening 2, 4 denotes a disk transfer power transmitting part for supplying the disk transfer part 3 with a driving power, 5 denotes a disk reproducing part arranged near inside center of the chassis 1 and 6 denotes a clamp arm for fixing the disk to the disk the disk reproducing part 5.
A reference numeral 7 denotes a disk size selecting lever that turns at a swing angle varying according to size (outside diameter) of the disk inserted through the disk inserting opening 2 to change a clamp position by the clamp arm 6 in response to outside diameter of the disk. The disk size selecting lever 7 can turn in a direction shown by an arrow A and in a direction shown by an arrow B around a turning axis 8 which is fixed to the chassis 1. And a pin 7a sliding on outer peripheral portion of the disk is provided at tip of the disk size selecting lever 7. Moreover, the disk size selecting lever 7 is urged by a coil spring 9 so as to always turn in the direction shown by the arrow B and thus it stands by at a position biased to a maximum extent in the direction shown by the arrow B in preparation for transferring the disk.
A reference numeral 10 denotes a sliding member that moves to a front position away from its original position (not shown) to retract a disk transfer member (not shown) from near the disk in preparation for a clamping operation by the clamp arm 6 of clamping the disk transferred to the clamp position. The sliding member 10 is mainly constituted by a first slider rack 11 sliding in a front and rear direction near the disk inserting opening 2 and a second slider rack 12 sliding in a front and rear direction on an original position (not shown) side. The first slider rack 11 is a long member having a rack 11a which engages with gear 4a of the disk transfer power transmitting part 4. Between the chassis 1 and a rear end portion nearer to the original position of the first slider rack 11 is provided a coil spring 13 for always urging the first slider rack 11 backward on the original position side. The second slider rack 12 is also a long member having a rack (not shown) which engages with gear 4a of the disk transfer power transmitting part 4. Between the chassis 1 and a rear end portion nearer to the original position of the second slider rack 12 is provided a coil spring (not shown) for always urging the second slider rack 12 backward on the original position side.
Next, an operation of loading a disk (not shown) will be described.
First, when the disk is inserted through the disk inserting opening 2, motor (not shown) of the disk transfer power transmitting part 4 is activated by a sensor (not shown) which is mounted on a board (not shown). And transfer roller 3a of the disk transfer part 3 is rotated in a direction of loading the disk (in a direction shown by an arrow C in FIG. 12) by the rotational driving power. Thereby the disk is transferred into the device. When the disk is transferred, its outer peripheral portion abuts against pin 7a of the disk size selecting lever 7. When the disk is further transferred, the pin 7a slides on outer peripheral portion of the disk, so that the disk size selecting lever 7 turns at a predetermined swing angle in the direction shown by the arrow A around the turning axis 8. When the disk size selecting lever 7 turns at the predetermined swing angle, it pushes a disk centering member 6a arranged on the clamp arm 6. By this arrangement, the disk can be transferred to a centering position (clamp position) suitable for its size. When transfer of the disk is completed, a member (not shown) for detecting a completion of transferring the disk pushes the first slider rack 11 to retract the disk transfer member (not shown). When the first slider rack 11 moves forward by a predetermined distance from the original position, its rack 11a engages with gear 4a of the disk transfer power transmitting part 4 and further moves forward. When the first slider rack 11 moves in this manner, it pushes and moves down transfer roller 3a of the disk transfer part 3. At the same time when the first slider rack 11 moves forward by a predetermined distance, the second slider rack 12 for moving down the clamp arm 6 to the disk reproducing part 5 side also moves forward in cooperation with the first slider rack 11. When the second slider rack 12 moves forward, a locking member (not shown) for locking the disk reproducing part 5 turns to unlock the disk reproducing part 5, thereby the disk reproducing part 5 can be prevented from being vibrated with respect to the chassis 1 by an elastic member (not shown). When it is detected by means (not shown) for detecting a quantity of movement arranged at a loading completion position that the second slider rack 12 moves to the loading completion position, the power supplied by the disk transfer power transmitting part 4 is stopped and a series of loading operations are completed.
Next, an operation of ejecting the disk will be described.
When the disk reproducing device receives a direction of ejecting the disk (not shown), the first slider rack 11 and the second slider rack 12 are moved by power along a direction of ejection (in a direction shown by an arrow D in FIG. 12) supplied by the disk transfer power transmitting part 4. Here, the second slider rack 12 is moved to a position where its rack (not shown) is disengaged from gear 4a of the disk transfer power transmitting part 4 and after this position, it is moved to an ejection completion position of the second slider rack 12 by a push applied by the first slider rack 11, where it is released from the push applied by the first slider rack 11. After the first slider rack 11 is moved to a position where rack 11a of the first slider rack 11 is disengaged from gear 4a of the disk transfer power transmitting part 4, it is moved to the ejection completion position (original position) by urging force of the coil spring 13. The disk is transferred by power transmitted to the disk transfer part 3 from the disk transfer power transmitting part 4 and it is detected by a sensor (not shown) that the disk is moved to the ejection completion position and the power supplied by the disk transfer power transmitting part 4 is stopped.
However, the conventional disk reproducing device is constituted in a manner described above, so that it has the following problem. That is, at the time of the ejection operation, for example, the first slider rack 11 is constituted in such a way that it returns to the original position by urging force of the coil spring 13 after its rack 11a is disengaged from gear 4a of the disk transfer power transmitting part 4. However, there is a case where the first slider rack 11 can not return to the original position because a sliding load is increased by warp and wear of the first slider rack 11 caused by a comparatively high temperature inside the chassis 1 of the disk reproducing device or the coil spring 13 is decreased in a spring load. In such case, there is happened a problem that a faulty operation will occur at the timing of an operation of loading the next disk.
In this respect, in order to stably attain a return of the first slider rack 11, there is also a method of simply setting spring load of the coil spring 13 at a higher value, but this higher spring load results in increasing a load to other mechanism and thus increasing a possibility of causing an operation stop, so that this method can not be adopted.